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2.
Can J Gastroenterol Hepatol ; 2022: 7499492, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439633

RESUMO

Background: Chronic hepatitis B (CHB) patients with normal or minimally increased levels of alanine aminotransferase (ALT) are still at the risk of hepatocellular carcinoma, cirrhotic events, and mortality. However, there is a debate over the initiation of antiviral treatment for these patients. This systematic review and mate-analysis aimed to explore this problem. Methods: MEDLINE (PubMed), EMBASE, Cochrane Central Register of Controlled Trials, and Web of Science databases were systematically searched for retrieving relevant studies with risk ratios (RRs) or risk differences (RDs) for virological changes between antivirus-treated and no antivirus-treated CHB patients with ALT levels less than two-fold of the upper limit of normal. Retrieved data ranged from January 1990 to October 2020. Results: Of 6783 abstracts screened, 9 studies met the criteria for inclusion in the systematic review and had a low risk of bias. Among studies that were involved in the meta-analyses, it was found that the rates of HBsAg loss (RR = 12.22, 95% confidence interval (CI): 4.28-34.95, P < 0.001), HBsAg seroconversion (RR = 19.90, 95% CI: 2.75-144.09, P=0.003), and undetectable HBV DNA (RR = 11.89, 95% CI: 2.44-57.89, P=0.002) were both higher in the antiviral treatment group compared with placebo or no treatment group. Subgroup analysis suggested that patients who received interferon (IFN)-based therapy were more inclined to achieve HBsAg loss (P=0.010), HBsAg seroconversion (P=0.020), and HBeAg loss (P=0.002). Conclusion: From a sizable population, it was revealed that CHB patients with normal or minimally increased levels of ALT could benefit from the antiviral therapy, especially those who received IFN-based treatment.


Assuntos
Hepatite B Crônica , Neoplasias Hepáticas , Humanos , Alanina Transaminase , Hepatite B Crônica/tratamento farmacológico , Antígenos de Superfície da Hepatite B , Antivirais/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico
3.
Int J Cancer ; 151(8): 1321-1334, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35579980

RESUMO

Hepatocellular carcinoma (HCC) is a severe disease with high mortality and global incidence. However, the interaction between the gut microbiome and combined immunotherapy for HCC is yet unclear. In this prospective clinical study, patients with unresectable HCC who had not received systemic treatment previously were recruited. Fecal and serum samples were collected at the baseline point and before each subsequent administration as specified. Between 20 October 2019 and 2 February 2021, 61 patients were screened for eligibility, of whom 35 patients were finally included in this study. Alpha diversity of fecal samples from patients who responded to immunotherapy was higher than that of nonresponders at baseline. However, the prominent alpha-diversity between responders and nonresponders became similar as early as week 6 after treatment. The beta diversity of intergroup did not show significant difference at the ninth week after treatment. Alpha-d-Glucose was the only serum metabolite that differed between the responders and nonresponders after 3 months. Responder-enriched Ruminococcus showed a positive correlation with serum galactaric acid, while Klebsiella was positively associated with 3-methylindole and lenticin (all P < .01). The machine learning classifier based on serum metabolites were more able to discriminate HCC patients who potentially benefited from immunotherapy at baseline (AUC 0.793, 95% CI: 0.632-0.954) than the classifier of gut microbiome. In conclusion, gut microbiome biomarkers are associated with the response to anti-PD-1 based immunotherapy in HCC patients. Classifiers based on gut microbiota and serum metabolites are feasible.


Assuntos
Carcinoma Hepatocelular , Microbioma Gastrointestinal , Neoplasias Hepáticas , Microbiota , Carcinoma Hepatocelular/tratamento farmacológico , Humanos , Fatores Imunológicos/uso terapêutico , Imunoterapia , Neoplasias Hepáticas/tratamento farmacológico , Metaboloma , Receptor de Morte Celular Programada 1/imunologia , Estudos Prospectivos
4.
Eur J Gastroenterol Hepatol ; 34(5): 576-584, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35131999

RESUMO

BACKGROUND/AIMS: In patients with acute-on-chronic liver failure (ACLF), type 1 hepatorenal syndrome (HRS) is a critical organ failure complication that resulted in rapid mortality. There are no efficient parameters to predict HRS in hepatitis B virus (HBV)-related ACLF. To assess HBV-ACLF risk factors and evaluate the association between mean arterial pressures (MAP), HRS and survival in patients with HBV-ACLF. METHODS: A total of 420 ACLF patients were screened from June 2015 to June 2016, and 57 HBV-ACLF patients were included in the study. Clinical data and MAP measurements of these patients were collected. Multivariate analyses, Cox proportional hazards regression and receiver operator characteristic (ROC) curves were used to analyze. RESULTS: In a 30-day study period, 43 (75.44%) patients survived. Patients in the HRS group were older and had higher Model for End-Stage Liver Disease (MELD) scores than patients in the non-HRS group. A MAP drop of ≥9.5 mmHg was an independent predictor of HRS with a sensitivity and specificity of 92.86 and 69.77%, respectively. The baseline MELD score was also an independent risk factor of HRS. MAP drop (OR, 1.582; P = 0.000), prothrombin time, HRS, MELD and FIB were independent prognostic factors for 30-day mortality. The area under the ROC curve of MAP drop was 0.808 (P = 0.001). CONCLUSION: A decrease in MAP was a valuable predictor of HRS in patients with HBV-related ACLF. MAP drop ≥9.5 mmHg may be useful for predicting patient prognosis and exploring new treatment measures in patients with HBV-related ACLF.


Assuntos
Insuficiência Hepática Crônica Agudizada , Doença Hepática Terminal , Síndrome Hepatorrenal , Hipotensão , Insuficiência Hepática Crônica Agudizada/diagnóstico , Insuficiência Hepática Crônica Agudizada/etiologia , Pressão Arterial , Doença Hepática Terminal/complicações , Feminino , Vírus da Hepatite B , Síndrome Hepatorrenal/diagnóstico , Síndrome Hepatorrenal/etiologia , Humanos , Masculino , Prognóstico , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
5.
J Clin Transl Hepatol ; 9(4): 503-513, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34447679

RESUMO

BACKGROUND AND AIMS: The safety and efficacy of mesenchymal stem cells (MSCs) in the treatment of acute-on-chronic liver failure (ACLF) have been validated. However, the impact of the pathological ACLF microenvironment on MSCs is less well understood. This study was designed to explore the changes in the functional properties of MSCs exposed to ACLF serum. METHODS: MSCs were cultured in the presence of 10%, 30% and 50% serum concentrations from ACLF patients and healthy volunteers. Then, the cell morphology, phenotype, apoptosis and proliferation of MSCs were evaluated, including the immunosuppressive effects. Subsequently, mRNA sequencing analysis was used to identify the molecules and pathways involved in MSC functional changes in the context of ACLF. RESULTS: In the presence of ACLF serum, MSC morphology significantly changed but phenotype did not. Besides, MSC proliferation activity was weakened, while the apoptosis rate was lightly increased. Most importantly, the immunosuppressive function of MSCs was enhanced in a low-concentration serum environment but transformed into a proinflammatory response in a high-concentration serum environment. RNA sequencing indicated that 10% serum concentration from ACLF patients mediated the PI3K-Akt pathway to enhance the anti-inflammatory effect of MSCs, while the 50% serum concentration from ACLF patients promoted the conversion of MSCs into a proinflammatory function by affecting the cell cycle. CONCLUSIONS: The 50% ACLF serum concentration is more similar to the environment in the human body, which means that direct peripheral blood intravenous infusion of MSCs may reduce the effect of transplantation. Combining treatments of plasma exchange to reduce harmful substances in serum may promote MSCs to exert a stronger anti-inflammatory effect.

6.
Aging (Albany NY) ; 13(6): 8563-8587, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33714200

RESUMO

Tumor mutation burden (TMB) has been associated with prognosis in various malignancies, but it has yet to be elucidated in hepatocellular carcinoma (HCC). We aimed to investigate the prognostic effects of TMB and its relationship with immune infiltration through multiple databases and whole-exome sequencing, so as to establish a panel model capable of predicting prognosis. The results demonstrated that the prognosis of high TMB group was worse than that of low TMB group, with a cutoff TMB value of 4.9. Enrichment analysis demonstrated that differentially expressed genes were mainly related to T cell activation, cell membrane localization and matrix composition. Tumor immune infiltration analysis revealed the infiltrations of Th2, Th17, and Tgd were up-regulated in high TMB group, while those of Tr1, MAIT, and DC were up-regulated in low TMB group. TMB-Infiltration model fit well with the actual survival observation, with a C-index 0.785 (0.700-0.870), which verified in ICGC-LIRI-JP was 0.650 (0.553-0.747). Additionally, these screened immune genes performed well in predicting tumor vascular invasion with a C-index of 0.847 (0.778-0.916). Overall, these results indicated that patients with high mutation frequency of immune-related genes and high TMB were prone to have worse prognosis and relapse after radical treatment.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Linfócitos do Interstício Tumoral/imunologia , Adulto , Idoso , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico
8.
J Exp Clin Cancer Res ; 38(1): 475, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31771611

RESUMO

BACKGROUND: Forkhead box G1 (FOXG1) is a member of the Fox transcription factor family involved in regulation of many cancers. However, the role of FOXG1 in hepatocellular carcinogenesisis largely unclear. The present study aimed at examining the biological function and underlying mechanism of FOXG1 on hepatocellular carcinoma (HCC) tumor metastasis as well as its clinical significance. METHODS: Levels of FOXG1 were determined by immunohistochemical and real-time PCR analysis in HCC cell lines and human HCC samples. The effect of FOXG1 on cancer cell invasion and metastasis was investigated in vitro and in vivo in either FOXG1-silenced or overexpressing human HCC cell lines. Immunoprecipitation and chromatin immunoprecipitation assays were performed to investigate the interaction of FOXG1, ß-catenin, TCF4 and the effect on Wnt target-gene promoters. RESULTS: In human HCC, the level of FOXG1 progressively increased from surrounding non tumorous livers to HCC, reaching the highest levels in metastatic HCC. Furthermore, expression levels of FOXG1 directly correlated with cancer cell epithelial-mesenchymal transition (EMT) phenotype. In FOXG1-overexpressing cells, FOXG1 promotes the stabilization and nuclear accumulation of ß-catenin by directly binding to ß-catenin and it associates with the lymphoid enhancer factor/T cell factor proteins (LEF/TCFs) on Wnt responsive enhancers (WREs) in chromatin. CONCLUSIONS: The results show that FOXG1 plays a key role in mediating cancer cell metastasis through the Wnt/ß-catenin pathway in HCC cells and predicts HCC prognosis after surgery. Targeting FOXG1 may provide a new approach for therapeutic treatment in the future.


Assuntos
Carcinoma Hepatocelular/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Via de Sinalização Wnt , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Fatores de Transcrição Forkhead/biossíntese , Fatores de Transcrição Forkhead/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Metástase Neoplásica , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Prognóstico , Transdução de Sinais , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Regulação para Cima , beta Catenina/metabolismo
9.
Cell Physiol Biochem ; 51(1): 470-486, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30453289

RESUMO

BACKGROUND/AIMS: MicroRNA-197 (miR-197) has been shown to play roles in epithelialmesenchymal transition (EMT) and metastasis. The Wnt/ß-catenin pathway is associated with EMT, but whether miR-197 regulatesWnt/ß-catenin remains unclear. This study was to demonstrate the role of miR-197 on the Wnt/ß-catenin pathway in hepatocellular carcinoma (HCC). METHODS: Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the expression of miR-197 in 105 HCC specimens and 15 HCC cell lines. We tested the predicted target gene of miR-197 using a genetic report system. The role of miR-197 in HCC cell invasion and migration (wound healingand cell invasion and migrationby Transwell assays) and in an HCC xenograft modelwas analyzed. RESULTS: Using a miRNA microarray analysis of HCC specimens and compared with non-metastatic HCC, miR-197 was identified as one of the most upregulated miRNAs in metastatic HCC. miR-197 expression was positively associated with the invasiveness of HCC cell lines. Metastatic HCC cells with high miR-197 expression had Wnt/ß-catenin signaling activation. High levels of miR-197 expression also promoted EMT and invasionHCC cells in vitro and in vivo. miR-197 directly targeted Axin-2, Naked cuticle 1 (NKD1), and Dickkopf-related protein 2 (DKK2), leading to inhibition of Wnt/ß-catenin signaling. High miR-197 expression was found in HCC specimens from patients with portal vein metastasis;high miR-197 expression correlated to the expression of Axin2, NKD1, and DKK2. CONCLUSION: miR-197 promotes HCC invasion and metastasis by activating Wnt/ß-catenin signaling. miR-197 could possibly be used as a prognostic marker and therapeutic target for HCC.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Via de Sinalização Wnt , Regiões 3' não Traduzidas , Proteínas Adaptadoras de Transdução de Sinal , Animais , Antagomirs/metabolismo , Antagomirs/uso terapêutico , Proteína Axina/antagonistas & inibidores , Proteína Axina/genética , Proteína Axina/metabolismo , Proteínas de Ligação ao Cálcio , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Interferência de RNA , RNA Interferente Pequeno/metabolismo
10.
BMC Gastroenterol ; 18(1): 61, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29743020

RESUMO

BACKGROUND: Hepatitis B virus (HBV) is a hepatotropic DNA virus, and its DNA may be a potent inflammatory molecule. Interferon-inducible protein 16 (IFI16), a newly discovered DNA sensor, plays an important role in the process of inflammation in viral infections. Our study sought to identify a correlation between IFI16 expression and inflammation in patients with chronic hepatitis B (CHB) and HBV-associated acute-on-chronic liver failure (HBV-ACLF). METHODS: We performed flow cytometry to measure IFI16 levels in peripheral blood mononuclear cells (PBMC) and used immunohistochemistry and western blotting to measure IFI16 protein levels in liver tissues. The cellular source of IFI16 was detected using double immunofluorescence. All datum were analyzed using SPSS 13.0 and GraphPad Prism 6. RESULTS: The number of IFI16+ cells was significantly associated with the degree of inflammation. In detail, the number of IFI16+ cells was higher in livers but lower in PBMCs in HBV-ACLF patients than those in CHB patients and healthy controls. There was no significant difference between CHB patients and healthy controls in numbers of IFI6+ cells in livers and PBMCs. There was no significant relationship between IFI16 expression levels and HBV parameters. Furthermore, IFI16 was expressed in the nucleus of Kupffer cells (KCs), endothelial cells, natural killer cells, dendritic cells, and hepatic stellate cells in healthy donors and CHB patients, but only in the cytoplasm of KCs in the livers of HBV-ACLF patients. CONCLUSIONS: IFI16 was closely related to the degree of inflammation in CHB and HBV-ACLF patients and may serve as a vital contributor to the pathogeneses of liver damage in HBV-ACLF.


Assuntos
Insuficiência Hepática Crônica Agudizada/metabolismo , Insuficiência Hepática Crônica Agudizada/patologia , Hepatite B Crônica/metabolismo , Hepatite B Crônica/patologia , Leucócitos Mononucleares/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Insuficiência Hepática Crônica Agudizada/etiologia , Adulto , Idoso , Citoplasma/metabolismo , Feminino , Expressão Gênica , Hepatite B Crônica/complicações , Hepatite B Crônica/genética , Humanos , Células de Kupffer/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Fosfoproteínas/genética
11.
Am J Phys Anthropol ; 163(3): 497-509, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28374460

RESUMO

OBJECTIVES: To describe the physical growth of healthy children under 7 years in China based on the latest national survey and provide more data for revising growth reference and monitoring the impact of social development on children's health and growth. METHODS: In the cross-sectional survey, 161,774 healthy children under 7 years were selected by multistage stratified cluster sampling method in nine cities of China. According to the geographical location, the nine cities were divided into northern, central and southern regions, and each city included urban and suburban areas. Anthropometric measurements were obtained on the spots and other related information was collected with questionnaires. RESULTS: There were slight urban-suburban difference and obvious regional difference in anthropometric measurements in China. Comparison with the 4th NSPGDC in 2005, measurements increased 0.1-1.1 kg in weight, 0.5-1.8 cm in height in urban areas (except children under 3 years) and 0.1-2.5 kg in weight, 0.2-3.8 cm in height in suburban areas. The urban-suburban difference of those measurements became smaller than 10 years ago, but their regional difference persistently exist. Chinese children were 0.36 SD in weight, 0.43 SD in height in urban areas and 0.30 SD in weight, 0.30 SD in height in suburban areas higher than WHO standards. CONCLUSIONS: Physical growth of children under 7 years old was undergoing a slowly positive secular trend during the latest decade in more economically developed regions of China. Urban-suburban difference of those measurements became smaller, while their regional difference persistently exist. Chinese healthy children under 7 years in nine cities was taller and heavier than WHO standards.


Assuntos
Estatura/fisiologia , Peso Corporal/fisiologia , Desenvolvimento Infantil/fisiologia , Gráficos de Crescimento , População Urbana/estatística & dados numéricos , Criança , Pré-Escolar , Estudos Transversais , Escolaridade , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Valores de Referência
12.
Chin J Cancer ; 34(5): 205-16, 2015 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-26058595

RESUMO

INTRODUCTION: Most hepatocellular carcinomas (HCC) develop in a background of underlying liver disease including chronic hepatitis B. However, the effect of antiviral therapy on the long-term outcome of patients with hepatitis B virus (HBV)-related HCC treated with chemoembolization is unclear. This study aimed to evaluate the survival benefits of anti-HBV therapy after chemoembolization for patients with HBV-related HCC. METHODS: A total of 224 HCC patients who successfully underwent chemoembolization were identified, and their survival and other relevant clinical data were reviewed. Kaplan-Meier and Cox regression analyses were performed to validate possible effects of antiviral treatment on overall survival (OS). RESULTS: The median survival time (MST) was 15.9 (95% confidence interval [CI], 9.5-27.7) months in the antiviral group and 9.6 (95% CI, 7.8-13.7) months in the non-antiviral group (log-rank test, P = 0.044). Cox multivariate analysis revealed that antiviral treatment was a prognostic factor for OS (P = 0.008). Additionally, a further analysis was based on the stratification of the TNM tumor stages. In the subgroup of early stages, MST was significantly longer in the antiviral-treatment group than in the non-antiviral group (61.8 months [95% CI, 34.8 months to beyond the follow-up period] versus 26.2 [95% CI, 14.5-37.7] months, P = 0.012). Multivariate analysis identified antiviral treatment as a prognostic factor for OS in the early-stage subgroup (P = 0.006). However, in the subgroup of advanced stages, MST of the antiviral-treated group was comparable to that of the non-antiviral group (8.4 [95% CI, 5.2-13.5] months versus 7.4 [95% CI, 5.9-9.3] months, P = 0.219). Multivariate analysis did not indicate that antiviral treatment was a significant prognostic factor in this subgroup. CONCLUSION: Antiviral treatment is associated with prolonged OS time after chemoembolization for HCC, especially in patients with early-stage tumors.


Assuntos
Antivirais , Carcinoma Hepatocelular , Quimioterapia Combinada , Vírus da Hepatite B , Prognóstico , Quimioembolização Terapêutica , Hepatite B Crônica , Humanos , Neoplasias Hepáticas , Mortalidade , Estadiamento de Neoplasias , Estudos Retrospectivos
13.
Mediators Inflamm ; 2015: 535938, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25892854

RESUMO

Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a rapidly progressing and frequently fatal condition. The aim of this study was to determine whether interleukin- (IL-) 33 and soluble ST2 (sST2) were associated with disease severity and mortality in HBV-ACLF. We found that plasma levels of sST2 but not IL-33 were higher in HBV-ACLF patients compared with chronic hepatitis B (CHB) patients and healthy controls. However, plasma levels of IL-33, TNF-α, IFN-γ, and IL-10 did not correlate with sST2 levels. Similarly, immunohistochemistry revealed low IL-33 expression and high ST2 expression in liver sections of patients with HBV-ACLF. Evaluation of dynamic changes of sST2 in HBV-ACLF showed that plasma sST2 levels increased over time in patients who died during the 180-day follow-up but decreased in those who survived. In addition, plasma sST2 level after week 1 correlated with disease severity, as assessed by total bilirubin, prothrombin time, and model for end-stage liver disease score. Results of Kaplan-Meier survival analysis showed that higher sST2 concentration (≥87 ng/mL) at week 3 was associated with poor survival. These findings indicate the potential usefulness of sST2 as a predictor of disease severity and in making treatment decisions for patients with HBV-ACLF.


Assuntos
Insuficiência Hepática Crônica Agudizada/sangue , Hepatite B Crônica/sangue , Receptores de Superfície Celular/sangue , Insuficiência Hepática Crônica Agudizada/mortalidade , Adulto , Bilirrubina/sangue , Biomarcadores/sangue , Biópsia , Estudos de Casos e Controles , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Vírus da Hepatite B , Hepatite B Crônica/mortalidade , Humanos , Imunoensaio , Imuno-Histoquímica , Proteína 1 Semelhante a Receptor de Interleucina-1 , Interleucina-33/sangue , Estimativa de Kaplan-Meier , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Curva ROC , Índice de Gravidade de Doença , Resultado do Tratamento
15.
J Chem Phys ; 137(4): 044108, 2012 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-22852598

RESUMO

The importance of the four-body contribution in compressed solid krypton was first evaluated using the many-body expansion method and the coupled cluster theory with full single and double excitations plus perturbative treatment of triples. All different four-atom clusters existing in the first- and second-nearest neighbor shells of face-centered cubic krypton were considered, and both self-consistent-field Hartree-Fock and correlation parts of the four-body interaction were accurately determined from the ambient conditions up to eightfold volume compression. We find that the four-body interaction energy is negative at compression ratio lower than 2, where the dispersive forces play a dominant role. With increasing the compression, the four-body contribution becomes repulsive and significantly cancels the over-softening effects of the three-body potential. The obtained equation of state (EOS) was compared with the experiments and the density-functional theory calculations. It shows that combination of the four-body effects with two- and three-body interactions leads to an excellent agreement with EOS measurements throughout the whole experimental range 0-130 GPa, and extends the prediction to 300 GPa.

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